Russia says it has taken control of the port in Mariupol and that more than 1,000 Ukrainian marines have surrendered in the south-eastern Ukrainian city.
The capture of the Azovstal industrial district, where the marines have been holed up, would give the Russians full control of Mariupol, Ukraine's main Sea of Azov port, reinforce a southern land corridor and expand Moscow's occupation of the country's east.
Surrounded and bombarded by Russian troops for weeks and the focus of some of the heaviest fighting in the war, Mariupol would be the first major city to fall since Russia invaded Ukraine on February 24.
Russia's defence ministry said 162 officers were among 1,026 soldiers of the 36th Marine Brigade who had surrendered to Russian and pro-Russian separatist forces near the Illich Iron and Steel Works.
Russian television showed pictures of what it said were marines giving themselves up, many of them wounded. One was shown holding a Ukrainian passport.
The Russian defence ministry later said Mariupol's trade seaport was under full control and remnants of Ukrainian forces were blocked and unable to escape, Russia's Interfax news agency reported.
The ministry said 151 wounded Ukrainian troops were treated on the spot and taken to Mariupol's city hospital.
Ukraine's general staff confirmed Russian forces were attacking Azovstal and the port, but a defence ministry spokesman said he had no information about any surrender.
Reuters journalists accompanying Russian-backed separatists saw flames billowing from the Azovstal area on Tuesday, a day after Ukraine's 36th Marine Brigade said its troops had run out of ammunition.
Vadym Denysenko, advisor to Ukraine’s Interior Minister, said Ukrainian forces were still fighting in Mariupol.
"The battle over the sea port is still ongoing today,” he said.
There was no immediate comment from the Ukrainian president's office.
On Monday, a post on the Ukrainian Marine Brigade's Facebook page had said the unit was preparing for a final battle in Mariupol that would end in death or capture as its troops had run out of ammunition.
"Today will probably be the ultimate battle, as there is no ammo left," said the post.
"Beyond that: hand-to-hand fighting. Beyond that, for some death, for others capture."
Some Ukrainian officials said at the time that the post may have been fake, and that troops were still holding out.
Thousands of people are believed to have been killed under a near-seven week siege of Mariupol.
Ukraine says tens of thousands of civilians have been trapped inside that city, with no way to bring in food or water, and has accused Russia of blocking aid convoys.
Earlier, Chechen leader Ramzan Kadyrov — an ardent supporter of Russian President Vladimir Putin — urged remaining Ukrainians holed up in Azovstal to surrender.
"Within Azovstal at the moment, there are about 200 wounded who cannot receive any medical assistance," Mr Kadyrov said in a Telegram post.
"For them, and all the rest, it would be better to end this pointless resistance and go home to their families."
Reuters
